BraLTP1, a lipid transfer protein gene involved in epicuticular wax deposition, cell proliferation and flower development in Brassica napus

PLoS One. 2014 Oct 14;9(10):e110272. doi: 10.1371/journal.pone.0110272. eCollection 2014.

Abstract

Plant non-specific lipid transfer proteins (nsLTPs) constitute large multigene families that possess complex physiological functions, many of which remain unclear. This study isolated and characterized the function of a lipid transfer protein gene, BraLTP1 from Brassica rapa, in the important oilseed crops Brassica napus. BraLTP1 encodes a predicted secretory protein, in the little known VI Class of nsLTP families. Overexpression of BnaLTP1 in B. napus caused abnormal green coloration and reduced wax deposition on leaves and detailed wax analysis revealed 17-80% reduction in various major wax components, which resulted in significant water-loss relative to wild type. BnaLTP1 overexpressing leaves exhibited morphological disfiguration and abaxially curled leaf edges, and leaf cross-sections revealed cell overproliferation that was correlated to increased cytokinin levels (tZ, tZR, iP, and iPR) in leaves and high expression of the cytokinin biosynthsis gene IPT3. BnaLTP1-overexpressing plants also displayed morphological disfiguration of flowers, with early-onset and elongated carpel development and outwardly curled stamen. This was consistent with altered expression of a a number of ABC model genes related to flower development. Together, these results suggest that BraLTP1 is a new nsLTP gene involved in wax production or deposition, with additional direct or indirect effects on cell division and flower development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Brassica napus / physiology*
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics*
  • Cell Proliferation
  • Flowers / physiology*
  • Gene Expression
  • Gene Expression Regulation, Plant
  • Genes, Plant*
  • Molecular Sequence Data
  • Phenotype
  • Plant Leaves
  • Sequence Alignment
  • Waxes / metabolism*

Substances

  • Carrier Proteins
  • Waxes
  • lipid transfer protein

Grants and funding

This work was supported by Major Research Project of CAAS Science and Technology Innovation Program, the National Natural Science Foundation of China (grant numbers 31400243 and 31201152) and the Natural Science Foundation of Hubei Province (grant number 2013CFB423). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.